I just took delivery of a pair of Nolan 103 helmets with the 584 Elite headset installed. First of all, let me say that it takes quite a bit of getting used to, but over all, I really like it and some of its features.
Down side: It's a very tight fit, due to very thick (but removable) cheek pads. I've heard that they will loosen up a bit, but if not, you might want to think of a size larger. I found that the thinner J&M speakers were still a bit too thick and rubbed against my ears. I had to remove the pad cover over the speakers and the Velcro holding them in, and that helped a bit. I think I'm going to have to remove the speakers and dig the "indent" a bit deeper to make it more comfortable. Getting comfortable with the mic seems to be a never-ending work in progress. There's very little room between the inside of the chin-bar and your mouth, so it's impossible to get the mic even close to your mouth. I ended up cutting away some of the Styrofoam on the inside of the chin-bar to provide a little pocket for the mic.
Up side: The modular system is the greatest. Very easy to flip up and back down..., and there's almost zero vibration when riding with the chin-bar and/or the face shield up, even at highway speeds. It has a terrific flip-down sunshade which is mounted INSIDE the helmet, so you can use it even if the chin-bar is up..., and it works very well. The entire lining can be easily removed for cleaning. The Elite 584 J&M system is outstanding. I keep the volume control set at about HALF of what I had with my previous system..., and the quality of music is really nice.
I'm still evaluating the 103, but so far, even with a few issues, I like it a lot.